


Synergy

by SeaOfClouds



Series: Rex/Emmet Requests [2]
Category: The LEGO Movie (2014), The LEGO Movie 2: The Second Part (2019)
Genre: Alternate Universe - Canon Divergence, M/M, Prompt Fic, Prompt Fill, Sharing a Body, Soul Bond
Language: English
Status: Completed
Published: 2019-05-27
Updated: 2019-05-27
Packaged: 2020-03-17 20:25:39
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,054
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18972367
Author URL: https://archiveofourown.org/users/SeaOfClouds/pseuds/SeaOfClouds
Summary: Rex had no idea what was happening, but for some reason, he had wound up in Emmet’s body. He didn’t even want to begin to think about how that was possible.But the question remained-- if Rex was here, then where the hell was Emmet?





	Synergy

**Author's Note:**

  * For [Mizu Cha](https://archiveofourown.org/gifts?recipient=Mizu+Cha).



“Wait, Rex-- come with us,” Emmet offered, holding out his hand.

“That ain’t how it works, kiddo,” He replied bluntly, staring down at his hands at they became enveloped in bright light.

“Rex...” Emmet started, lost for words as he struggled to process what was happening to the other.

“It’s okay. I’m proud of you. You’re gonna grow up to be better than me,” He told his younger self, with regret and hope in his eyes.  “But kind of thanks to me, so... I’m also great,” he added with a smirk.

“No!” Emmet yelled, pulling the time traveller into a crushing embrace, “You can’t leave. I won’t let you.”

“Hey... It’s okay,” Rex offered, patting his back as best he could, as his arms began to fade. “You’ll be fine.”

“No, I won’t let you die,” the younger man was stern with his words, as he fought back tears, burying his face in the other man’s neck.

“I’ll see you around.”

Those were the last words Emmet heard before he fell forward to his knees, arms now empty and wrapped around himself. He stared at the ground in shock. He just-- couldn’t understand.

Why... Why couldn’t he save him? Why did it have to be this way?

It wasn’t fair to either of them.

As his tears began to flow freely, he covered face with his hands, unable to hold back a sob that escaped his lips.

“I’m sorry Emmet,” Lucy said with a hand on his shoulder, “Let’s go home.”

 

~o~o~o~o~o~

 

When Rex awoke, it was dark. He blinked, squinting at his surroundings. Where was he?

As he struggled to sit upright, he began to see things that were familiar. The bedside table, the window with a dull slither of light peeking through-- that’s right, he’s back at home. In his bed.

Of course he is.

A sudden wave of nausea assaulted his stomach, causing him to leave the room quickly in search of the bathroom. He gripped to the sink tightly, waiting for the feeling to dissipate, sweat forming on his brow.

He eventually loosened his grip, running the tap and splashing his face a few times for good measure.

For some reason, he couldn’t for the life of him remember how he got here. Or what he had done the previous day. It felt as if he had been in a dream for several years, having only just woken now.

But that was... impossible.

Rex turned and reached for the nearest towel, drying off his face as he stared at his reflection in the mirror.

Only, it wasn’t his reflection. And it wasn’t someone he recognised.

He unintentionally jumped back in surprised, hitting the door behind him with a thud as he continued to stare at himself in confusion. He blinked, bringing a hand up to his face to run down the side, feeling the texture of his face, and watching the reflection do the same.

Rex looked... younger. His hair was shorter, face a little pudgier than he remembered. He looked so similar to Emmet, but not quite-- as if the younger man had somehow aged a few years overnight.

But that didn’t explain why Rex was here, staring into a mirror at a face that wasn’t his.

A headache hit him full force out of nowhere, causing him to hold his head in his hands. It was as if a switch gone off-- the memories of the previous day flooding back.

They were on Undar... He vanished.

Then... What was he doing here?

He... he died.

In Emmet’s arms.

How--

Rex flinched at the sound of a knock, coming from the other side of the bathroom door.

“Emmet, are you okay in there?” Lucy asked, sounding half asleep but her tone was full of concern.

It was just as he feared. Rex had no idea what the hell was happening, but for some reason, he had wound up in Emmet’s body-- which had somehow even changed in appearance as well. He didn’t even want to begin to think about how that was possible.

But the question remained-- if Rex was here, then where was Emmet? Was he... somewhere? Anywhere?

Did this mean that Emmet was... gone?

Rex shook his head. No, no... That couldn’t possibly happen. Rex was from the future, Rex was the one that changed the course of the past and screwed it up, causing himself to cease to exist. Emmet was fine-- he was supposed to be fine, to continue to live without him.

All things considered, it was almost as if the two of them had... merged together.

That-- that couldn’t be possible... could it?

Was there a way for the minds and bodies of two people to merge into one? Surely not... that was _ridiculous_.

“Ye--” Rex coughed, noting his voice was still low. He collected himself, remembering how to change his voice back, “Yeah, just, not feeling too good.”

He heard a slight shuffling, before she responded, “Alright. Let me know if you need anything.”

“Sure,” was all Rex could think to say, grateful that she was giving him some space.

He took a seat on the side of the bathtub, holding his hands together in a firm grip. What was he going to do? He barely had any understanding of what was happening himself, let alone trying to explain it to someone else. What would Lucy do once she realised that he’s Rex and not Emmet?

Rex leaned forward, resting his elbows on his thighs as he held his face in his hands. He focused on his breathing, making the best attempt to not freak out. He couldn’t afford to do that. At least, not yet.

Maybe, if he sat here and tried to clear his thoughts, he could figure this out.

He wasn’t sure how long he stayed like that. It could have been hours, it could have been just minutes.

But then, he heard something.

_Hello?_

~o~o~o~o~o~

 

Emmet felt so heavy, as if gravity had increased overnight, causing his limbs to fight against him as he struggled to sit upright.

The floor beneath him was solid, yet no matter how hard he tried, he couldn’t figure out what it was.

He brought a hand up to his eyes, rubbing them in an attempt to focus on something, anything, in his immediate vicinity. Yet he continued to look around and see nothing but black, stretching on for infinity.

Emmet held his hands close as he stood up, trying hard not to panic.

Had he... Was he blind? Why couldn’t he see anything?

He took a few steps forward, arms outstretched as he felt around. After a few metres, he became more confident in his movements, speeding up until he was sprinting.

There was... nothing. He was nowhere. There was just constant eternal emptiness.

He collapsed, legs shaking so violently that they refused to work any longer.

Where was he? Why was he alone? He didn’t like this.

For the life of him, he couldn’t even remember how he ended up here. The last thing he remembered was seeing Rex disappear in his arms, as he was overcome with grief.

And then... nothing.

Losing his sight was one thing-- losing his hearing, or voice was another. He wasn’t sure why he ended up here, but he wasn’t going to give up easily.

“Hello?” Emmet said hesitantly into the abyss, relieved that he did still have his senses intact.

The only response to his question was an echo, as his voice travelled into the unknown abyss.

Having run out of ideas, he shifted to sit in a more comfortable position, contemplating his options. He concluded that, at this stage, he had exactly _zero_.

Emmet just hoped that, wherever he was, his friends would come to rescue him soon.

 

~o~o~o~o~o~

 

Rex was so startled by hearing the voice of his younger counterpart, that he fell backwards into the bathtub rather gracelessly, hitting his head in the process.

Was-- was that Emmet?

He looked around the room as he scrambled upright, eyes flicking in every direction. That was most definitely his voice, he’d recognise it anywhere. But... he wasn’t here.

So how could he hear him?

Unless...

Another knock at the door grabbed Rex’s attention, forcing him to climb out of the tub and get back on his feet.

“Yeah?” He asked hesitantly.

“I’m going out to the shops, will pick you up something while I’m gone. Just, make sure to get some rest, yeah?”

Rex grimaced, thankful for her kind words but still afraid of the inevitable, “Thanks, Lucy.”

After a few minutes of listening by the door, he made sure he heard the sound of the front door closing, before he made a move.

If that really was Emmet’s voice, then there’s only one thing he could think of.

They were sharing a body, somehow - two different consciousnesses in the same mind. As terrifying and confusing as that was, Rex needed to do something about it quickly.

And he knew just the guy to help him out.

 

~o~o~o~o~o~

 

“Sir, you have a visitor,” the young officer spoke after opening the door to Bad Cop’s office, Rex standing awkwardly behind her.

Bad Cop looked up with surprise, before waving them in. Rex took a seat, just as Good Cop switched out, “Hey Emmet, how can I help you?”

“I need your help,” Rex replied in his own voice.

The cop’s brow furrowed, concerned. “Help with what?”

Rex sighed, running a hand down his face. How were you supposed to open such a conversation?

“I’m... not Emmet. I’m Rex,” he pointed to himself.

Good Cop blinked. “I.... don’t understand.”

“Look, I-- I’m Rex, and I’m pretty sure I died yesterday, and now I’ve woken up and Emmet is nowhere to be found, and I don’t recognise myself-- and I have no clue what the hell is happening.”

The cop continued to look at him as if he was insane, which was a reasonable response.

“I couldn’t make this shit up if I tried,” Rex added.

“How did this happen?” Good Cop queried, studying him.

“You’re guess is as good as mine. I have some suspicions, but... I have a feeling it may be similar to your situation with Bad Cop. I think he might be... in my head.”

The cop hummed, looking Rex up and down. “There aren’t many reported cases, but...” He trailed off, thinking. “Could it be possible...?”

“Don’t keep me hanging here,” Rex commented, become frustrated.

“If Emmet wanted you to stay, more than anything, then-- it’s quite possible he bound your soul to him.”

Rex’s eyebrows could not possibly go any higher on his forehead, as he stared in shock at the words.

“So-- what you’re saying is, he practically willed me to continue existing? To prevent me from disappearing?”

“We believe so. But I imagine, if he’s woken up-- he’d most certainly be terrified.”

“What... do you mean?” He asked with a sceptical face.

Good Cop stared intently at him. “Where do you think the other one of us goes when we switch?”

“I... I’m guessing it’s not somewhere lovely and colourful?”

The cop looked sorrowful. “We’re used to it, and switch often. Sometimes, we can even sleep while the other is awake. But still, if you’re not used to it, or know how to control it... it can be difficult to adjust.”

Rex swallowed, feeling his confidence disappearing the more he spoke.

“Okay, so-- how do I get in contact with Emmet, then?”

“Close your eyes,” Good Cop pulled up the chair next to Rex, sitting in front of him. “Tell me, where are you?”

The time traveller tensed, looking around. “I’m not sure... It’s all black.”

“Good. You’re in your mind-space.”

Rex looked around, every direction he could think of. There was nothing. Why was there nothing? Why was it all so empty?

“You need to keep calm. It’s difficult to do this when you’re not familiar with it yet.”

“Okay,” Rex replied hesitantly. “I’ll try.”

Good Cop cleared this throat, “Now, think of a door. Make that the focus of your thoughts. You should see one behind you now.”

“I...” He felt scared, but he wasn’t sure why. It must have been obvious on his features.

“I need you to relax. Focus on the door, and let your mind go.”

Rex exhaled sharply as he turned, relieved to see a door behind him, the only thing appearing to exist in this space. He walked towards it with curiosity, inspecting it.

“What is it?” The time traveller asked.

“Two minds in one body is difficult to handle. The door allows your minds to be separated, so memories and thoughts remain your own. But this door is also used to talk to each other, and, to switch on command,” the cop explained.

Rex simply nodded in response, eyes staring intently at the door handle. “So do I just, open it? That’s it?”

Good Cop hummed, “You can try. It might not open for you yet. Try knocking on it instead.”

Was he serious? Knocking on a make-believe door in his mind? Guess he had nothing to lose at this point.

Rex sighed, complying with the request and standing there in a few moments of silence.

“H-hello?” A familiar yet hesitant voice responded.

“Emmet? Is that you!?” Rex yelled, placing his hands upon the door.

“Rex!? W-what’s happening? Where are we?” Emmet was panicking, pulling on the door handle to no avail. “Why can’t I see you? Are-- are we dead?”

“Hey, it’s okay, relax. We’re fine, you’re alive,” Rex responded softly. “I can’t open the door. But I need you to calm down, otherwise it will only make things more difficult. This may be hard to believe, but... we’re in your mind-space.”

“We’re... in my head?” The concern and confusion in his voice was prominent.

“Yeah, I guess you can put it like that.”

“I suppose that makes sense. But why are you here? Are you a figment of my imagination?”

Rex chuckled, leaning back against the door. “Sorry kiddo, I’m the real deal.”

He heard the other man go quiet for a moment. “B-but how is that possible? You-- I saw you die.”

“Hey, I’m just as confused as you are. But I’ve been talking to Good Cop, considering our similar circumstances, and we’re still trying to figure this all out,” He sighed, the extensive conversation beginning to tire him out. “I wanted to make sure we could talk to let you know what’s happening.”

“So the reason I woke up here, is because we’re sharing the same body?”

“Something like that, yeah,” Rex replied bluntly. “But your physical appearance has also changed, somehow. You can imagine how confused I was when I woke up this morning. Haven’t even told Lucy yet.”

“But... how could that happen?”

“Well, Good Cop has his suspicions. Apparently, it’s possible to fuse your soul with that of another, when you’re in a heightened emotional state. Much like what we went through yesterday.”

Emmet was quiet for a while, concerning Rex-- he couldn’t be sure if the other was still there or not. He probably just needed more time to process.

“I brought this on us, didn’t I?” The younger man said, sounding defeated. “I just... couldn’t let you go.”

Rex smiled, “Didn’t realise how much you cared about me. I am grateful, all things considered. But I can’t go around living inside your body. I’m here to switch.”

“And then what?” Emmet asked, “You’re just going to stay here, in the back of my mind, forever?”

“Best I can do right now, kiddo. It’s your body, your life.”

“Surely there’s another way,” Emmet bargained.

“We’ll have time to figure that out later. For now, I need you to work with me.”

“Just tell me what to do.”

“Hold on the handle of the door, and focus. I think if we can... sync our minds, then we’ll be able to open the door.”

The younger man sighed, “Okay Rex. I’ll try.”

A silence fell between the two of them, both of their focus intent on the task at hand. Rex’s grip was so firm on the door that he felt he may break it. He needed to do this, though, for Emmet’s sake.

Something overcame him, something hard to describe-- it felt almost tranquil.

In that moment he knew what he had to do, turning the handle of the door and pulling it forward.

A bright light enveloped him, before it all went dark.

 

~o~o~o~o~o~

 

Emmet sat upright with a start, breathing heavily as if he had been suffocated. He brought a hand up to his chest, gripping to his vest as he regained control of his body.

A hand was on his shoulder, keeping him steady. He looked up to see the familiar face of Good Cop.

“Emmet?” He asked with concern.

The construction worker simply nodded in reply, struggling to regain his composure.

They did it-- they switched. He was back, he was in control.

But Rex-- he was stuck there, in the darkness, alone. He had to do something to help him, to save him.

“Rex...?” He asked, staring at the floor. He wasn’t sure if he had to speak out loud, or if there was some way for them to talk internally - but he was willing to try anything.

_I’m here, kiddo. Don’t worry about me-- I’m fine._

Emmet sighed in relief, glad to hear the other’s voice. Their ordeal, in their mind-space, had been exhausting, taking a toll on him. Both mind and body.

He felt like he could very happily go back to sleep for another few days.

“I’m so glad that worked,” Good Cop commented, sitting down next to Emmet with a sigh. “Did he fill you in on the details?”

“Yeah... I think so,” he replied, adjusting to the feeling of having someone else in his head. It was like nothing he could ever explain. “What now?”

The cop hummed thoughtfully, considering their options, “I think it’s best to talk to Unikitty. Her knowledge in the supernatural and magic in general would help us out right about now.”

Emmet nodded in agreement, “Lead the way.”

 

~o~o~o~o~o~

 

“This isn’t just a soul-merge,” Unikitty started, studying Emmet with curiosity, walking around him a few times, “Their physical form has been merged as well.”

Emmet blinked, unsure how to respond. Lucy was by his side in an instant, placing a reassuring hand on his shoulder.

“So is that a good thing or a bad thing?” She asked with concern.

“Well, it means separating them will be easy, as they still have their own physical body to inhabit,” Unikitty placed her hands on her hips, thinking intently. “The tricky part is figuring out how to undo it.”

She turned around, moving to a bookshelf in the corner of the room, and began scanning each row of books. Occasionally, she’d pull the spine of one, sometimes removing the book and placing them on her desk nearby.

“I think I’ve got it,” Unikitty stated with excitement. “Emmet, I need you to stand here, in the centre of the room.”

He simply nodded, doing as she directed. He needed to make sure this would work, for the sake of both of them.

“Rex? Are you still there?” The construction worker questioned, feeling nervous at his counterpart’s silence.

_Yeah, I’m still here. Not like I’ve got many places to go. What’s happening out there?_

Emmet sighed, composing himself, “We think we might have figured out how to separate us, but I’m guessing whatever it is will require us to focus like we were before.”

_No problem. Ready when you are._

Unikitty returned, standing a pace away from Emmet. She appeared deep in thought, focusing on the task at hand.

“I need you to close your eyes, and focus on Rex. This is important, so ensure your mind does not wander during the spell.”

Emmet nodded as he closed his eyes - he could do that. Thinking about Rex was all he had been doing all day.

She held out one of her hands, placing it only an inch away from Emmet’s chest. Looking down to at the book in other hand, she began to read something out loud-- something he couldn’t understand, like an incantation.

The longer she spoke, the more nervous he felt. What if it didn’t work? What if it just made things worse?

No, he couldn’t think like that-- he needed to focus. _Think about Rex_.

Unikitty’s voice gradually became louder as she read the final line of the text. Her hand near Emmet’s chest retracted, before returning full force, slamming into his chest with all her strength.

The pain was brief, but it felt as if a huge weight had been released from his mind, exiting as quickly as it came. He felt someone holding onto him, preventing him from falling backwards.

Emmet opened his eyes slowly, staring at a rather surprised Unikitty and Lucy in front of him, who were looking behind him in unison. He turned to follow their gaze, settling on the familiar form of Rex, passed out on the floor.

“Rex!” He yelled, unintentionally loud. He was surprised that it had worked, and thankful that his friend could help-- but right now, he needed to make sure Rex was okay.

The construction worker practically jumped on the other, grasping his vest firmly and shaking him gently, an attempt to get the other to wake. When it didn’t appear to work, he moved one of his hands, to his neck, checking for a pulse.

He was alive.

Emmet let out a loud breath, having not realised he was holding it in. He was here, they were separate, but he needed to know-- had his mind also been separated?

He nearly jumped as he felt the time traveller move beneath him, hand coming up to grab Emmet’s as he mumbled something incoherent.

“...Emmet?” He asked, attempting to sit up and regain his bearings. “The hell happened...?”

He didn’t have a chance to respond, focus changing behind him as he felt a hand on his shoulder.

“Okay, so, due to what’s occurred between the two of you, I need you to stay here and talk to each other just to make sure everything is in the correct consciousness,” Unikitty explained, flicking through another one of her books. “We’ll be back in a few hours to check on you.”

She smiled as she wrangled the others, pushing them all out the room with her. As she closed the door, she winked at Emmet-- who in return simply smiled, unsure what she was implying with the gesture.

“ _Fuck_ , that hurt. Did I get punched in the chest or something?” Rex asked.

Emmet turned his attention back to Rex, who was still sitting in the centre of the room.

“Yeah, sorry about that-- would have given you a warning if I knew it was coming,” He commented light-heartedly, taking a seat on the floor next to the other. “How do you feel?”

“Exhausted. Like I haven’t slept in months.”

“Same here,” Emmet replied, eyes gazing away. “I’m sorry for causing so much trouble.”

“Don’t worry about it kiddo, we’re fine now,” Rex said as he leaned back, hands moving behind him for balance. “That was one hell of an experience.”

“You know, it’s funny,” Emmet started with a blush, “I do kind of miss it.”

Rex raised an eyebrow, “Are you _serious_?”

He shrugged, “It was strange in a way-- it was nice having someone in your head to talk to.”

The time traveller laughed. His counterpart could be adorable when he wanted to be.

“Well, I suppose now that we’re separated, I can do this,” the younger man said next him, piquing his curiosity.

The time traveller turned to him to question his statement, just as Emmet latched onto his vest, pulling him forward into a chaste kiss.

“I’m glad you’re okay, Rex,” He said, pulling the other into a warm embrace.

Rex stared in disbelief, waiting for his mind to catch up with what had just occurred, before smiling and returning the gesture.

“Yeah. Me too.”


End file.
